Sediment Toxicity Monitoring S

1
Sediment Toxicity Monitoring ST program
1993-2005

• Toxicity is persistent in the Estuary and more
  frequent in the northern and southern regions.
• Between 1997-2001
• 67 of ST sediment samples were toxic to either
  species
• Eohaustorius (amphipod)
• Mytilus (bivalve larvae)

2
Change in the ST Experimental Design in 2000
Less toxicity seen in the summer
3
New Proposal
The TRC asked us to develop a new proposal that
focused on getting at what might be causing the
persistent sediment toxicity observed in the
Status and Trends Program Get review and
comments from the Toxicity Workgroup
4
The Toxicity Workgroup met (Nov. 27th)

• Endorsed the overall proposal
• Liked the standard 10-day estuarine amphipod
  test
• Focus on Bay-margins in the winter
• New sediment TIE methodology is well developed
• Study is consistent with what the workgroup had
  proposed in past
• Want to participate in developing the site
  selection criteria
• and the prioritized list of sites to
  investigate

5
Sediment TIE Study Proposal
TIEs will be conducted with the estuarine
amphipod Eohaustorius estuarius. The goal of
this study is to use newly-developed sediment TIE
methods to determine the possible causes of
sediment toxicity at the margins of the Estuary.
6
Sediment TIE Study Proposal

• Develop a list of sampling sites
• Screen sites to locate two toxic sites
• Conduct the TIE study at these sites

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Sediment TIE Study Proposal

• - Three phase sediment TIE
• Characterization
• Identification
• Confirmation

- Bulk sediment and pore-water samples - Standard
EPA toxicity methods for estuarine sediments
(E. estuarius 10-day survival)
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Sediment TIE Study Proposal

• Develop a list of sampling sites

9
Sediment TIE Study Proposal
2. Screen sites to locate two toxic
locations Sample first four sites if
toxic conduct TIEs, Chemistry assess
duration If not toxic sample four more sites
if toxic conduct TIEs, and
Chemistry
10
Sediment TIE Study Proposal
2. Screen sites to locate two toxic
locations Sample first four sites if
toxic conduct TIEs, Chemistry assess
duration If not toxic sample four more sites
if toxic conduct TIEs, and
Chemistry
If none of the eight sites are toxic enough to
warrant a full TIE, sample last four sites
(after) if toxic conduct TIEs, and Chemistry
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Summary
- Develop a prioritized list of sites
(12) - Sample first four
-4 if toxic
conduct TIEs, Chemistry and assess duration - If
not toxic sample four more sites
-4 if toxic conduct TIEs, and Chemistry If
none of eight sites are toxic consult TRC for
approval of four more sites in 2008 - Sample last
four sites
-4 if toxic conduct TIEs, and Chemistry
0
12
Budget
2007 Episodic Toxicity Budget
140,000 Sediment TIE Study Proposal 2007
96,600